I'm not very familiar with the RFVC engines, other than having a basket case xr500 pass through my shop while I was transporting it for a buddy. I did end up looing it over pretty good hoping to "borrow" a few parts for my non RFVC 500 before discovering that there is zero parts interchaingability.

But I do know that on an older single you are very likely to have some valve spring collapse. It dosen't cost anything to pull the valves and measue the valve springs, and stock springs are pretty cheap, way cheaper that risking floating the valves till they interfere with the piston. If you have a top end gasket kit it likely has valve stem seals and pulling the valves will then let you install the new seals.

I think your idea of trying to get it runing before spending much on it is sound, but once it is running how likely are you to pul it apart if you hear something? or would you be tempted to run it into the ground? I know how tempting it is to just ride a cheap dirt bike till it dies.

I think your idea of trying to get it running before spending much on it is sound, but once it is running how likely are you to pull it apart if you hear something? or would you be tempted to run it into the ground? I know how tempting it is to just ride a cheap dirt bike till it dies.

I actually am pretty good about being kind to my machines and fixing them the right way (not like I was when I was 16 that's for sure). I figure if it actually does run 'ok' AND all the parts are there, then I have the rest of the winter to figure out what else it may need. I also want to get it to a point to see whether it can be titled/registered (even if I push it to DMV, Ha, they're only 2 blocks away - obviously needs to be together for this to happen). I can also budget myself instead of a giant chunk of money right at the beginning, without even knowing if the whole bike is in the 'proverbial baskets'. Gaskets are pretty cheap and my time costs me nothing... My wife and I are also in the middle of purchasing a house so I REALLY want it together (and at least able to be rolled around) before we move. I hate moving basket cases from one point to another. Seems like something always gets lost or damaged. So, maybe not the best way to do it, but that's ok. I may be broke but I'm patient .

I'm loving this ADVRider forum BTW, really like reading all the info about these bikes. Learning something new every day. Had NO idea these bikes should be pre-oiled because of airlock issues in the oil pump setup before post rebuild startup, for example. Or, all the different ways to install the timing chain tensioner. Or, the stripped headbolts issue - happened to me, but helicoiled it to the tune of about 25$ - and still have extra coils and tools for the next time it goes bad. Just all sorts of little tips to make a successfully running bike.

I have to say, a close friend of mine bought a brand new KTM to the tune of around 10,000$ (he's a serious rider/racer so I'm not begrudging him this). That being said, I could throw A LOT of money into a used bike, have a completely rideable bike, and have no where near that kind of money into it. In fact, in my lower income bracket, a 10K bike would completely be out of my price range for now and forever. I'm not saying that a person can't buy a bike for that kind of money, more power to them, but I freak out when I spend 4000$ on a car! So, this kind of bike is really fun, educational and very economically practical. I have had many bikes over the years, fought with most of them but had fun with all of them. Every one of them was some kind of project.

My favorite was a CB360T found 'basket case' in a chicken coop. I was at a garage sale, saw a frame for 75$. Asked the guy if the engine was available. He said it's in the chicken coop. Sure enough, a taken apart 360 engine, complete with chicken poop. Got the whole thing together and rode it for several years - then sold for a decent profit!

Anyway, now I'm just rambling, but again, thanks for the info! All of it is being assessed and certainly helps.

Chain on, valve cover on, all torqued and looking/feeling good! oil pump installed. I'm assuming the gear to the outside of the cam chain gear (I guess primary drive gear?) has the 'bump' mark to the outside as correct position? no other marks on it, but seems like Honda likes the marks to be out? Also, how does one torque the clutch nut w/o special tools or air?

Valve clearance feels good, and although I will adjust them, that is a good sign. Means haven't been run tight and/or nothing is weird with them burned, warped, etc. etc. This weekend is my wifes birthday. I guess I'd better 'tread lightly' and not get too involved with the bike.

Lock up anything rotating in relation to the clutch and then apply a torque wrench with appropiately sized socket tot the clutch nut, then bend the washer to lock it in place, if so equipped.

The only thing I'm surprised about in this build is the lack of a hone job and new rings. But I suppose it won't burn TOO MUCH oil.

What is the opinion of more seasoned experts in the line of piston rings and hones on reassembly? I have usually been told the two are mandatory upon disassembly of any internal combustion engine, whether 2 or 4 stroke. Although come to think of it, 2 stroke engine 50ccs I think I may have re-used the same rings, but without much noticeable smoking since it was 2-stroke, but also without much noticeable compression loss since I never checked it. Thoughts?

Lost roundness (round shape) of the cylinder and the rings
in the long work of the motor. (in the direction of the swing rod). Rings can not be set at the old place after the removal of the from motor. This is not good.
Measurements are required.

I had a base gasket leak happen on my 88 xr600...new piston and oem rings maybe had 2k miles on it...

so on the advice of an EXPERT I was told to replace gasket and reinstall it all back again...

he specifically said that the rings dont know jack squat if they are in or out of the cylinder...I didnt even realign the rings since the rings naturally rotate in the cylinder under normal engine running

since it was a fresh rebore and hone and rings and piston there was no need to rehone anything

however in the op's case this would be reccomended since he is dealing with original worn out parts...

in my case no compression loss and absolutely no smoking...

also I dry install pistons and rings now after a sort of bad incident with oiling the rings too much on my first rebuild...

he specifically said that the rings dont know jack squat if they are in or out of the cylinder...I didnt even realign the rings since the rings naturally rotate in the cylinder under normal engine running"

cheers

...I agree with this, I've always understood that the rings rotate in the bore as the engine runs, so it's a loss/gain of 0 when reinstalling the same rings and not honing... Whether it smokes or not, depends on if it smoked before PO took it apart.

...I agree with this, I've always understood that the rings rotate in the bore as the engine runs, so it's a loss/gain of 0 when reinstalling the same rings and not honing... Whether it smokes or not, depends on if it smoked before PO took it apart.

and, I could be wrong... I'll keep everyone posted on the outcome tho! :)

.....I hate moving basket cases from one point to another. Seems like something always gets lost or damaged......

This is so true. On the xl500 basket case that I picked up and transported for a buddy it came to me sans the seat, cam, and cam chain. I still have his front and rear fender but I reaized that as I was unloading everything from my truck into his garage. Then yeasterday I found a rear brake backing plate that is not from any of my bikes.

The rings don't really rotate. There isn't really any force in the engine to rotate them. We are always advised anywhere we look to position the ring end gaps away from each other to minimize blow-by, why would that be done if the rings rotated? I think every time i have disassembled an engine, the ring end gaps have been away from each other, as installed. Some pistons have a positioning pin to keep them from rotating, but any rotation of a piston ring is like 1mm per 60,000 miles.

And yes, in the case of a piston that has not seated to it's freshly honed bore, sure, maybe skip the hone and new rings. But if the bike has a thousand miles on it, this has been seated and worn to a shine and needs replacement.

cylinders dont get shiny after a thousand miles on the hone at all(mine wasnt)...takes a long time for that to happen

second the ring end gaps are positioned like honda says to so as to avoid any issues after the rebuild...or for the breakin milkes so you dont get any blow by...

the rings do move...since they ALL move its likely that they all are relatively in the same position when rebuilt...the actual piston has a circular motion to it...there is a little play at the rod, a little at the pin...etc...

anyways

a set of rings and a deglazing with even a ball hone would be better than nothing...